Lentigo maligna (Hutchinson freckle) and lentigo maligna melanoma are a subtype of melanoma that is almost exclusively seen on the chronically sun-damaged skin of elderly white persons. Lentigo maligna is the in-situ phase, whereas the term lentigo maligna melanoma is applied when clear-cut dermal invasion can be seen.
It makes up about 4% of cutaneous melanomas in the US. Most commonly involved sites are malar region, nose, temple, and forehead. It develops as a slowly enlarging, irregular, variably pigmented (brown or black) macule. It may have hypopigmented or pink-tan areas representing regression. The invasive tumor develops 10 or more years after in-situ lesion appears.